//
// Created by wze-zero on 2024/10/20.
//
#include <iostream>

using namespace std;

double check(int num) {
    if (num > 60) {
        return 0.2;
    } else {
        return 0.1;
    }
}

int main() {
    int n, num;
    double money = 0;
    cin >> n;
    for (int i = 0; i < n; ++i) {
        cin >> num;
        money += check(num);
    }
    cout << money << endl;
    return 0;
}